Yeah, I had the same issue. Which is weird because it existed in DOS2. Seems like an oversight on their part.
I also could not understand the toggle on top for Trade/Barter. No clue what changing it to trade does.
Its explained on one of loading screens, witch is kind of a bad way to place a "tutorial" as we do not have one for trading. I guess its expected from players to know such things from the get go. How to trade.
^kind of this. But barter is exchange goods for goods and that is all I know, I have no clue how value of goods or worth and amounts of said items are determined.